Some programs and features that are included with Windows, such as Internet Information Services, must be turned on before you can use them. Certain other features are turned on by default, but you can turn them off if you don’t use them.
In earlier versions of Windows, to turn a feature off you had to uninstall it completely from your computer. In this version of Windows, the features remain stored on your hard disk, so you can turn them back on if you want to. Turning off a feature does not uninstall the feature, and it does not reduce the amount of hard disk space used by Windows features.
Open the Control Panel, click Programs, click Turn Windows features on or off in the Programs and Features section (see picture above). Or,.. press the Windows button, type OptionalFeatures and press Enter.
To turn a Windows feature on, select the check box next to the feature.
To turn a Windows feature off, clear the check box.